If you’re struggling to enable any of the functions (system, exec, popen etc) by disabling safe mode, then you’re going down the wrong path. You need to change the disabled_functions key in php.ini instead.
; This directive allows you to disable certain functions for security reasons. ; It receives a comma-delimited list of function names. This directive is ; *NOT* affected by whether Safe Mode is turned On or Off. disable_functions = system,dl,passthru,chown,popen,proc_open